SLASEG6B May 2018 – June 2020 TAS3251
The sample rate converter supports 32 kHz, 44.1 kHz, 48 kHz, 88.2 kHz and 96 kHz input sample rates. These input sample rates are converted to 88.2 or 96 kHz sample rate. The sample rate detection doesn’t distinguish between sample rates from 32 to 48 kHz. These sample rates are treated as 48 kHz by the sample rate converter. The detected sample rate can be read at book 0x78 page 0x0C register 0x5C. The input sample rate is 88.2 or 96 kHz at register 0x5C which reads 0x00 00 00 01. The input sample rate is 32 to 48 kHz at register 0x5C which reads 0x00 00 00 02. Input sample rate 32 kHz requires changing the interpolation setting from 2x to 3x by writing B0-P0-R37-D7 to 1. The device must be placed in standby mode for this change to take effect.
|SAMPLING RATE (KHZ)||B0-P0-R91-D[6:4]|
|32 – 48||011|
|88.2 – 96||100|
|176.4 – 192||101|
Even though the sample rate converter supports 32 kHz, 44.1 kHz, 48 kHz, 88.2 kHz and 96 kHz input sample rates, the TAS3251 device supports all input sample rates shown in Table 26 in 1x interpolation mode, base rate processing.
The SRC input should not be overdriven. Making the maximum signal level into the SRC –0.5dBFs is recommended to prevent overdriving the SRC and causing audio artifacts. The input scale and mixer can be used to attenuate or boost the maximum input signal to –0.5dBFs. The processing block has several blocks after the SRC where the signal can be compensate for any gain attenuation done in the input mixer and scale block to prevent over driving the SRC.